diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c index c1d434ba3642c34fa7100740c643d45b392f6a7b..64c74334f7d0005d900ee40f368b782d644cf0ad 100644 --- a/drivers/pci/controller/dwc/pci-imx6.c +++ b/drivers/pci/controller/dwc/pci-imx6.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include #include @@ -77,6 +78,7 @@ struct imx6_pcie { u32 tx_swing_low; int link_gen; struct regulator *vpcie; + void __iomem *phy_base; /* power domain for pcie */ struct device *pd_pcie; @@ -134,6 +136,23 @@ struct imx6_pcie { #define PCIE_PHY_RX_ASIC_OUT 0x100D #define PCIE_PHY_RX_ASIC_OUT_VALID (1 << 0) +/* iMX7 PCIe PHY registers */ +#define PCIE_PHY_CMN_REG4 0x14 +/* These are probably the bits that *aren't* DCC_FB_EN */ +#define PCIE_PHY_CMN_REG4_DCC_FB_EN 0x29 + +#define PCIE_PHY_CMN_REG15 0x54 +#define PCIE_PHY_CMN_REG15_DLY_4 BIT(2) +#define PCIE_PHY_CMN_REG15_PLL_PD BIT(5) +#define PCIE_PHY_CMN_REG15_OVRD_PLL_PD BIT(7) + +#define PCIE_PHY_CMN_REG24 0x90 +#define PCIE_PHY_CMN_REG24_RX_EQ BIT(6) +#define PCIE_PHY_CMN_REG24_RX_EQ_SEL BIT(3) + +#define PCIE_PHY_CMN_REG26 0x98 +#define PCIE_PHY_CMN_REG26_ATT_MODE 0xBC + #define PHY_RX_OVRD_IN_LO 0x1005 #define PHY_RX_OVRD_IN_LO_RX_DATA_EN (1 << 5) #define PHY_RX_OVRD_IN_LO_RX_PLL_EN (1 << 3) @@ -533,6 +552,26 @@ static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie) break; case IMX7D: reset_control_deassert(imx6_pcie->pciephy_reset); + + /* Workaround for ERR010728, failure of PCI-e PLL VCO to + * oscillate, especially when cold. This turns off "Duty-cycle + * Corrector" and other mysterious undocumented things. + */ + if (likely(imx6_pcie->phy_base)) { + /* De-assert DCC_FB_EN */ + writel(PCIE_PHY_CMN_REG4_DCC_FB_EN, + imx6_pcie->phy_base + PCIE_PHY_CMN_REG4); + /* Assert RX_EQS and RX_EQS_SEL */ + writel(PCIE_PHY_CMN_REG24_RX_EQ_SEL + | PCIE_PHY_CMN_REG24_RX_EQ, + imx6_pcie->phy_base + PCIE_PHY_CMN_REG24); + /* Assert ATT_MODE */ + writel(PCIE_PHY_CMN_REG26_ATT_MODE, + imx6_pcie->phy_base + PCIE_PHY_CMN_REG26); + } else { + dev_warn(dev, "Unable to apply ERR010728 workaround. DT missing fsl,imx7d-pcie-phy phandle ?\n"); + } + imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie); break; case IMX6SX: @@ -994,6 +1033,7 @@ static int imx6_pcie_probe(struct platform_device *pdev) struct device *dev = &pdev->dev; struct dw_pcie *pci; struct imx6_pcie *imx6_pcie; + struct device_node *np; struct resource *dbi_base; struct device_node *node = dev->of_node; int ret; @@ -1013,6 +1053,23 @@ static int imx6_pcie_probe(struct platform_device *pdev) imx6_pcie->pci = pci; imx6_pcie->drvdata = of_device_get_match_data(dev); + /* Find the PHY if one is defined, only imx7d uses it */ + np = of_parse_phandle(node, "fsl,imx7d-pcie-phy", 0); + if (np) { + struct resource res; + + ret = of_address_to_resource(np, 0, &res); + if (ret) { + dev_err(dev, "Unable to map PCIe PHY\n"); + return ret; + } + imx6_pcie->phy_base = devm_ioremap_resource(dev, &res); + if (IS_ERR(imx6_pcie->phy_base)) { + dev_err(dev, "Unable to map PCIe PHY\n"); + return PTR_ERR(imx6_pcie->phy_base); + } + } + dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0); pci->dbi_base = devm_ioremap_resource(dev, dbi_base); if (IS_ERR(pci->dbi_base))